Wisdom Tooth Extraction — How It Works, Benefits & Recovery — Procedure Guide, Recovery & Risks | MyMedicPlus

Wisdom tooth extraction is a common oral and maxillofacial surgical procedure to remove one or more of the four third molar teeth — the last teeth to erupt in the permanent dentition, typically between the ages of 17 and 25 — when they are causing disease, are at high risk of causing disease, or are causing significant symptoms due to failure of complete eruption into the dental arch. Third molars become impacted — unable to fully erupt into a normal functional position — in approximately 30-40% of the population, most commonly in the mandible (lower jaw). Impaction classification by Winter describes angulation: mesioangular (the most common, angled forward toward the second molar), horizontal (at 90 degrees to the adjacent tooth), distoangular, and vertical. The Pell and Gregory classification grades depth of impaction (Class I, II, III) and relationship to the anterior border of the ramus (Class A, B, C), together determining surgical difficulty and risk of neurovascular complications. Lower impacted third molars in close proximity to the inferior alveolar canal (IAC) — confirmed on panoramic radiograph by overlapping roots, narrowing of the canal, deflection of the canal, or darkening of the roots — may require cone beam CT (CBCT) imaging before surgery to precisely quantify nerve-to-root distance and plan the safest extraction approach. The procedure is performed by general dentists for simpler erupted teeth or by oral and maxillofacial surgeons for complex impactions.

Wisdom tooth extraction is indicated when the tooth is causing or has a high probability of causing a specific disease state or clinical problem. Evidence-based indications include pericoronitis — recurrent infection of the partially erupted tooth and surrounding gum tissue (operculum), causing localised pain, trismus, halitosis, and systemic signs in severe cases; dental caries or periodontal bone loss on the wisdom tooth itself or on the adjacent second molar caused by the impacted tooth's position; dentigerous cyst formation around the crown of an impacted tooth; external root resorption of the adjacent second molar caused by pressure from the impacted tooth; and pathological fracture risk in the mandible if the tooth occupies a significant proportion of the bone cross-section. Orthodontic space management prior to or following orthodontic treatment may indicate extraction of wisdom teeth causing crowding or undermining orthodontic results. Prophylactic extraction of asymptomatic, caries-free, non-infected impacted third molars remains controversial. NICE guideline TA1 (2000, reviewed 2023) recommends against routine prophylactic removal of disease-free impacted third molars because benefits are uncertain and surgery carries defined risks. However, some guidelines support early prophylactic removal before age 25, when root development is incomplete and the bone is more elastic — facilitating easier extraction with lower complication rates.

Simple erupted wisdom tooth extraction: the tooth is elevated from its socket using dental elevators to expand the periodontal ligament space and luxate the tooth, then removed with extraction forceps in a controlled rotational or buccolingual motion. Surgical extraction of impacted wisdom teeth proceeds as follows. Anaesthesia: inferior alveolar nerve block and lingual nerve block (lower teeth), or posterior superior alveolar and long buccal nerve blocks (upper teeth) using 2% lidocaine with 1:80,000 adrenaline. Intravenous conscious sedation with midazolam plus fentanyl, or general anaesthesia in day surgery, is used for anxious patients, multiple simultaneous extractions, or complex cases. Incision and flap: a mucoperiosteal flap is elevated — an envelope flap or three-sided flap — to expose the overlying alveolar bone. Bone removal: a surgical handpiece (straight or contra-angle) with a round or fissure bur removes the cortical bone overlying the tooth crown, and a bone window is created to provide access. Tooth sectioning: the tooth is divided with a bur into separate crown and root sections (mesial, distal, or both roots separately) to facilitate atraumatic removal of each component from the socket. Forceps and elevators are used to deliver each section. Socket irrigation with sterile saline removes bone debris. Flap closure: resorbable sutures (3-0 Vicryl or chromic gut) are placed to reapproximate the gingival margins. Coronectomy — intentionally leaving roots behind when they are intimately associated with the inferior alveolar canal — is an evidence-based alternative to reduce permanent inferior alveolar nerve (IAN) injury risk in selected cases.

Surgical extraction of symptomatic impacted wisdom teeth permanently resolves the precipitating indication in over 99% of cases. Pericoronitis — recurrent in over 70% of patients who experience a first episode — is definitively cured by extraction, eliminating a persistent source of bacterial infection and inflammation that can compromise adjacent second molar periodontal health. Extraction before the development of dentigerous cyst preserves bone volume and prevents the extensive jaw surgery required to treat established large cysts. Removal of impacted teeth causing adjacent second molar root resorption stops the otherwise progressive loss of the second molar — a much more valuable and difficult-to-replace tooth than the wisdom tooth itself. Younger patients (under 25 years) benefit from easier surgery with incompletely formed roots, more elastic bone, better post-operative healing, and lower risk of inferior alveolar nerve injury compared to patients over 35 where roots are fully formed, closely approximating the inferior alveolar canal, and bone is less elastic. Coronectomy in patients with high IAN risk reduces the rate of permanent inferior alveolar nerve sensory deficit from 5-20% (full extraction in high-risk cases) to under 1%, preserving normal lower lip and chin sensation.

Dry socket (alveolar osteitis) is the most common post-operative complication, occurring in 2-5% of routine lower third molar extractions and rising to 25-30% in heavy smokers. It results from premature dissolution or displacement of the blood clot from the extraction socket, leaving bare bone exposed to the oral cavity, causing severe aching pain starting 3-5 days post-operatively; treatment involves socket irrigation with warm saline and placement of a medicated iodoform-based dressing (Alvogyl or zinc oxide eugenol) changed every 2-3 days until re-epithelialisation occurs. Inferior alveolar nerve (IAN) injury causes numbness or altered sensation (paraesthesia or dysaesthesia) of the ipsilateral lower lip, chin, and teeth: temporary disturbance occurs in 1-8% of extractions, resolving completely within 6-8 weeks in most patients; permanent sensory deficit affects under 1% but is significant and distressing. Lingual nerve injury — causing tongue numbness and altered taste — is rarer but reported in 0.2-0.6% of lower third molar surgeries. Secondary haemorrhage occurs in 1-2% and is managed with local haemostatic measures. Post-operative infection and osteitis require antibiotic therapy. Fracture of the mandibular angle — rare (under 0.5%), most common with very deep impacted teeth in the angle region — may require open reduction and internal fixation. Damage to the adjacent second molar root occurs in under 1%.

Immediately after extraction, firm gauze pad pressure is applied to the socket for 20-30 minutes to promote clot formation. The blood clot must not be disturbed during the first 24-48 hours: patients must avoid rinsing the mouth vigorously, spitting forcefully, using straws, or touching the socket. After 24 hours, gentle warm saline mouth rinses (half teaspoon of salt in a glass of warm water) are performed after meals and at bedtime to keep the socket clean. Swelling peaks at 48-72 hours and is substantially reduced by intermittent ice pack application (20 minutes on, 20 minutes off) during the first 24-48 hours post-operatively. Analgesic management with regular paracetamol 1000 mg four times daily plus ibuprofen 400 mg three times daily (alternating) provides effective multimodal analgesia superior to either drug alone. A soft diet — avoiding hard, crunchy, or chewy foods — is maintained for 7-10 days for lower wisdom teeth. Resorbable sutures dissolve in 7-14 days without removal. Smoking must be absolutely avoided for at least 72 hours (ideally 7 days) as it dramatically increases dry socket risk by inducing fibrinolysis of the blood clot through nicotine and heat effects. Physical exertion, alcohol, and hot foods or beverages are avoided for 24-48 hours. Healing of the soft tissue takes 3-4 weeks; complete bony infilling of the socket takes 3-6 months.